Ceratozamia sancheziae: a Highland Cycad of Chiapas, Mexico

Ceratozamia sancheziae is a cycad of Mexico, endemic to the highlands of Chiapas (Los Altos de Chiapas), where it grows in oak and pine-oak forests between about 1,000 and 1,540 m (about 3,280 to 5,050 ft) according to the 2022 monograph of the genus, or between 1,500 and 1,800 m according to its original description. This species of the genus Ceratozamia was described in 2021 under the spelling Ceratozamia sanchezae, since corrected to sancheziae: both names refer to the same plant. Its populations were previously included in Ceratozamia robusta, from which they differ in narrower leaflets, fewer leaves and an almost unarmed petiole. The IUCN has not yet assessed it.

Key facts about Ceratozamia sancheziae

Accepted name: Ceratozamia sancheziae Pérez-Farr., Gut.Ortega & Vovides (2021), accepted by The World List of Cycads (version 2026.08.15) and by the World Checklist of Vascular Plants (WCVP, the database behind POWO, read via GBIF)
Former names and synonyms: published as Ceratozamia sanchezae (orthographic variant, corrected); populations formerly identified as Ceratozamia robusta
Family: Zamiaceae, order Cycadales
Common names: none recorded, in English or in Mexico (2022 monograph)
Natural range: Mexico, highlands of Chiapas (municipalities of Tenejapa and Altamirano), 1,000 to 1,536 m according to the 2022 monograph (1,500 to 1,800 m in the original description)
IUCN status: Not Evaluated (NE); the 2022 monograph suggests Endangered (EN) as a preliminary assessment
CITES and other protection: CITES Appendix I (whole genus, since 1985); Annex A in the European Union, seeds included
Documented hardiness: no data, neither from cultivation nor as temperature records from its habitat (see Cold hardiness)
Light and soil: in the wild, the understorey of oak, pine and sweetgum forests, on luvisols and phaeozems, often on very steep slopes (about 60°); no published growing advice
Habit and adult size: short trunk, 8 to 30 cm long, partly buried; 4 to 12 leaves (up to 20), 1 to 2.3 m long
In the UK, US and Australia: no garden declares it (see In cultivation)
Toxicity: no data for the species; treat it as poisonous, like all cycads (see Toxicity and precautions)

How to recognise Ceratozamia sancheziae

It is a medium-sized species with a short trunk and long, drooping leaves set with thin, linear leaflets. Compared with Ceratozamia robusta, it has fewer leaves and leaflets, a shorter rachis, arching leaves in adult plants, a sparsely armed petiole and smaller male cones (Gutiérrez-Ortega and colleagues, 2021). The 2022 monograph, which redefined the species, describes it as follows:

Trunk: 8 to 30 cm long and 10 to 20 cm across, half buried, upright; cataphylls reddish brown, covered in brown down when they emerge.
Leaves: 4 to 12, sometimes up to 20, 100 to 232 cm long, drooping; green or brown when they emerge, covered in whitish-grey hairs, then hairless. Petiole 40 to 134 cm long, unarmed or carrying 2 to 28 slender prickles under 4 mm long; rachis 55 to 120 cm long, unarmed or nearly so.
Leaflets: 20 to 35 pairs, linear, papery, green, bluish-white beneath, with clearly visible veins; the middle ones measure 22 to 36 cm by 1.7 to 3 cm.
Male cones: solitary, cylindrical, upright, 15 to 20 cm long and 1.8 to 3.2 cm across, light green, then green with blackish hairs.
Female cones: solitary, upright, 12 to 25 cm long and 7 to 8.5 cm across, yellowish green, then green; scales with straight or curved horns 5 to 7 mm long.
Seeds: globose, 1.9 to 2.3 cm long, with yellowish-white flesh turning light brown.

The original description states that young plants have oblanceolate leaflets; in the field, the authors of the monograph found only juveniles with linear leaflets. Young plants look more like those of the Ceratozamia miqueliana complex than like Ceratozamia robusta (Gutiérrez-Ortega and colleagues, 2021).

The original description, based on the plants of Tenejapa and of the localities then assigned to the species, gives similar but not identical measurements: a half-buried trunk 9 to 23 cm long and 10 to 20 cm across; 4 to 16 leaves 106 to 226 cm long, ascending then arching, light green or light reddish brown when they emerge; leaflets in 15 to 31 pairs, linear to lanceolate, sickle-shaped in their outer half, the middle ones 28 to 40 cm by 1.8 to 3.3 cm; female cones 18 to 28 cm long; and ovoid seeds 2.2 to 2.6 cm long. The sharpest difference concerns the male cone: 25 to 28 cm long and 8.9 to 10 cm across in the original description, against 15 to 20 cm by 1.8 to 3.2 cm in the monograph, which does not comment on the discrepancy. Both sets of figures are given here without deciding between them.

Hybrids

No natural or garden hybrid has been documented.

Possible confusion

The two confusions to watch for are with Ceratozamia robusta, in which the species was long included, and with Ceratozamia zoquorum, which grows in the same mountains of northern Chiapas.

Ceratozamia robusta: a larger plant with more leaves, a well-armed petiole and broader leaflets; its typical populations grow at middle elevations in central Chiapas (Gutiérrez-Ortega and colleagues, 2021). Ceratozamia sancheziae differs in its linear leaflets, its light green or reddish-brown new leaves with a bluish bloom, and the horns of its female cone scales, curved to straight and no more than 7.3 mm long (Martínez-Domínguez and colleagues, 2022).
Ceratozamia zoquorum: oblong, leathery leaflets, 4 to 5.6 cm wide and few in number (6 to 17 pairs), against linear, papery leaflets no more than 3 cm wide and more numerous (20 to 35 pairs) in Ceratozamia sancheziae (Martínez-Domínguez and colleagues, 2022).

Without cones, a young Ceratozamia is hard to tell from a Zamia; a label with the wild origin remains the best guide.

Taxonomy

Ceratozamia sancheziae is accepted by The World List of Cycads and by the WCVP, the database behind POWO (read via GBIF on 30 October 2026), which records it from south-eastern Mexico. The story of the name has three stages: separation from Ceratozamia robusta, correction of the spelling, and the redefinition of the range by the 2022 monograph.

A species split from Ceratozamia robusta

In 2021, José Said Gutiérrez-Ortega, Miguel Ángel Pérez-Farrera, Andrew Vovides and their co-authors published in Phytotaxa a study of the variation of Ceratozamia robusta. They measured ten leaf and trunk characters on 97 adult plants from six populations. Their analyses separated three groups: populations similar to the neotype of Ceratozamia robusta, at middle elevations in Chiapas; a large form at low elevations in Belize; and the populations of the Chiapas highlands, which differ from both. The highland group was described as a new species, and the authors noted that the variation of the characters follows elevation. The Belize plants were themselves described in 2022 as a separate species, Ceratozamia osbornei, by the authors of the monograph of the genus.

sanchezae or sancheziae?

The species was published as Ceratozamia sanchezae. The World List of Cycads and the International Plant Names Index (IPNI, checked on 30 October 2026) spell it sancheziae. The International Code of Nomenclature sets out how to form an epithet honouring a person: when the name ends in a consonant, an i is added before the ending, here -ae for a woman. Sánchez therefore gives sancheziae. The correction changes neither the authors, nor the date, nor the plant: it is the same taxon, and both spellings are found in the literature and in the trade.

The 2022 redefinition

The monograph of the genus published in 2022 by Lilí Martínez-Domínguez and colleagues revisited the species after fieldwork around Tenejapa, Altamirano, Tila and Yajalón. It divided the populations of this region between Ceratozamia sancheziae and Ceratozamia zoquorum, extended the range of the former south to Altamirano, but found no matching population near Yajalón or Tila, where several paratypes had come from. The authors also point out that a place given as a municipality in the original description is in fact a locality of the municipality of Tila. In their view, only a population study, with cones and molecular data, will show which species the Yajalón plants belong to.

The authors of the monograph did not find the type specimens of the species in the herbaria they consulted. The original description settles the type number: the holotype is the collection Pérez-Farrera 3558 (a female plant, Tenejapa, 1,500 m, 16 May 2017, HEM herbarium; isotypes at XAL and MEXU), as the monograph states; the collection Pérez-Farrera 1673, also from Tenejapa and given as the type by The World List of Cycads, appears there only among the paratypes. The other paratypes are two collections by Dennis Breedlove and two from Yajalón (MEXU), the very ones the monograph considers doubtful.

A 2024 study of the evolution of cone characters places Ceratozamia sancheziae among the few species of the genus whose female cone has become smaller in the course of evolution, along with Ceratozamia zoquorum and Ceratozamia santillanii (Martínez-Domínguez and colleagues, 2024).

Etymology and history

The epithet honours the Mexican biologist María Ydelia Sánchez-Tinoco. The original description acknowledges her work on reproductive biology, particularly the anatomy of the ovule and archegonia of cycads; The World List of Cycads, following Jody Haynes’s etymological compendium (2022), cites cycad reproductive biology, and the 2022 monograph her research on the anatomy of the seeds of Mexican cycads.

The type, a female plant, was collected on 16 May 2017 in the municipality of Tenejapa, at 1,500 m; the holotype is kept at the HEM herbarium (Tuxtla Gutiérrez), with isotypes at MEXU and XAL. Older collections exist: the monograph cites a specimen from Tenejapa collected in 1972 by Dennis Breedlove. No source documents the introduction of the species into cultivation.

Common names

No common name is recorded in English, and the 2022 monograph records no vernacular name in Mexico. The name Ceratozamia robusta, under which these plants used to be filed, should no longer be applied to them.

In the wild

Ceratozamia sancheziae is endemic to the state of Chiapas, Mexico. It grows in oak forest and pine-oak forest between 1,000 and 1,536 m, in the municipalities of Tenejapa and Altamirano (Martínez-Domínguez and colleagues, 2022). No climate data specific to its sites have been published.

The original description places it in oak, pine and sweetgum forest (Breedlove’s 1981 classification), between 1,500 and 1,800 m, with species such as Quercus candicans, Quercus rugosa, Quercus sapotifolia, Pinus oocarpa, Liquidambar styraciflua, Nyssa sylvatica, the palm Chamaedorea carchensis and epiphytes such as Tillandsia guatemalensis. It grows there on luvisols and phaeozems, generally on very steep slopes of about 60°, where Cretaceous marine sedimentary rocks crop out. The 2022 monograph, which adds the Altamirano populations, gives lower elevations (1,000 to 1,536 m) without commenting on the difference.

The monograph estimates that each population holds 70 to 250 adult plants. No study of pollination, germination or population dynamics has been published for the species.

Conservation status and regulation

Ceratozamia sancheziae has not yet been assessed by the IUCN (Not Evaluated, according to The World List of Cycads, confirmed by GBIF on 30 October 2026). The 2022 monograph suggests listing it as Endangered (EN), given the small number of populations and their size, 70 to 250 adults each. This is only a proposal, with no official standing.

Like the whole genus, it has been covered by CITES Appendix I since 1 August 1985 (the genus had been in Appendix II since 1977), and by Annex A of Regulation (EC) No 338/97 in the European Union (annexes now set by Regulation (EU) 2026/1383, applicable since 29 June 2026), seeds included. Species+ does not yet list the species under its own name (checked on 30 October 2026), but the listing covers the entire genus. International trade in wild-collected plants for commercial purposes is banned; only artificially propagated plants with the required permits can be traded.

In practice, the species is almost absent from the trade. Buy only seed-grown plants with documents of origin, and note the name under which they are sold: sancheziae, sanchezae or, for older plants, robusta. This general information does not replace the official texts: check the regulations in force before buying, importing or exchanging plants.

Growing Ceratozamia sancheziae

No source describes the cultivation of this species, and no cultivation report has been documented. The pointers below are drawn only from its habitat and from the general rules for the genus; they have not been confirmed by published trials.

Light: partial shade or filtered light, as in the oak understorey where it grows; avoid harsh sun.
Soil: free-draining and rich in organic matter; Ceratozamia dislike roots standing in cold water.
Watering: regular during growth, less frequent in winter, never leaving water standing.
Space: the adult leaves, more than 2 m long and drooping, need room.

Outdoor and in-ground cultivation

No outdoor planting of this species has been documented anywhere.

Container cultivation

For lack of data, a pot that can be moved under cover in winter is the safest option, in a free-draining mix rich in organic matter.

In cultivation in the UK, US and Australia

No botanic garden in the United Kingdom, the United States or Australia declares this species: BGCI PlantSearch lists no garden under either spelling, and the online catalogue of Montgomery Botanical Center lists no accession (both queried on 30 October 2026). Plants of the Chiapas highlands grown before 2021 may carry the name Ceratozamia robusta.

Propagation

Propagation is from seed. Like all cycads, the species has separate male and female plants; in cultivation, hand pollination is needed to obtain fertile seed. No germination data specific to the species have been published. Handle seeds wearing gloves.

Pests and diseases

No pest or disease specific to Ceratozamia sancheziae has been documented. In cultivated Ceratozamia, growers mainly report rot in cold, sodden soil and leaf scorch after sudden exposure to full sun.

Cold hardiness

No data exist for Ceratozamia sancheziae: no cultivation report, and no published temperature record from its sites. Its altitude, 1,000 to 1,800 m depending on the source, is not enough to infer frost tolerance.

Mediterranean and European experience

No cultivation of this species has been reported in Europe, and the Jardin zoologique tropical in La Londe-les-Maures (Var, on the French Riviera) has published no observation of it. European results for the genus concern other species and cannot be transferred to it.

United Kingdom, United States and Australia

No dated cold record and no commercial hardiness rating have been published. Until documented trials exist, grow it in a pot and overwinter it frost-free.

Toxicity and precautions

No toxicity study specific to Ceratozamia sancheziae has been published. The risk is well documented in other cycads: their tissues, and above all their seeds, contain toxic glycosides (cycasin, macrozamin), from which methylazoxymethanol is derived, a compound harmful to the liver and nervous system. In the absence of evidence to the contrary, treat the plant as poisonous: keep seeds and leaves out of reach of children and animals, wear gloves to clean seeds, and if any part is swallowed, call a poison centre, a doctor or a vet straight away.

Traditional uses

The 2022 monograph reports that the community of Tenejapa uses the leaves of the species to decorate traditional festivities. No further detail is given: neither the local name of the plant, nor the festivities concerned, nor the scale of the harvest.

Frequently asked questions

Are Ceratozamia sanchezae and Ceratozamia sancheziae the same plant?

Yes. The species was published in 2021 as sanchezae, which the rules of nomenclature correct to sancheziae. The World List of Cycads and IPNI use the corrected form; both spellings are still seen.

Is it a former Ceratozamia robusta?

Yes, in part. The populations of the Chiapas highlands were filed under Ceratozamia robusta until 2021. A study of their measurements showed that they form a distinct group, then described as a new species.

Where does it grow?

In the highlands of Chiapas, Mexico. It lives in oak and pine-oak forest between about 1,000 and 1,540 m according to the 2022 monograph (1,500 to 1,800 m according to the original description), in the municipalities of Tenejapa and Altamirano.

How can I recognise it?

By its thin, linear leaflets. It carries 20 to 35 pairs of leaflets no more than 3 cm wide, on drooping leaves with a sparsely armed petiole. Ceratozamia zoquorum, a neighbour, has much broader and fewer leaflets.

Is it endangered?

Probably, but it has not been assessed. The 2022 monograph suggests listing it as Endangered because its populations are few. Like the whole genus, it is listed in CITES Appendix I.

Can it take frost?

Nobody knows. No documented trial exists, and its highland forests are no guarantee of frost tolerance: overwinter it frost-free.

Sources

Reference sites

The World List of Cycads (version 2026.08.15), Ceratozamia sancheziae: https://cycadlist.org/scientific_name/903 — authors, place of publication, spelling, type, range (Chiapas), IUCN status (NE), etymology. Checklist of the IUCN Cycad Specialist Group, reliable; reread on 30 October 2026.
World Checklist of Vascular Plants (WCVP, Royal Botanic Gardens, Kew), via GBIF, Ceratozamia sancheziae: https://api.gbif.org/v1/species/207874412 — accepted name, place of publication (Phytotaxa 500: 209, 2021), south-eastern Mexico. Kew data, the basis of POWO, distributed by GBIF; consulted on 30 October 2026.
IPNI (International Plant Names Index), Ceratozamia sancheziae: https://www.ipni.org/n/77219235-1 — corrected spelling, publication, etymology. Reference nomenclatural index; consulted on 30 October 2026.
Phytotaxa, description of Ceratozamia sanchezae (2021): https://doi.org/10.11646/phytotaxa.500.3.4 — study of the variation of Ceratozamia robusta, three groups, distinguishing characters. Peer-reviewed journal; primary source.
Plazi TreatmentBank, treatment of Ceratozamia sanchezae (Gutiérrez-Ortega and colleagues, 2021): https://treatment.plazi.org/id/03FCB4583C38FF8999823590FA5244F0 — taxonomic part of the original description (holotype and paratypes, diagnosis, description, habitat, soils, etymology). Faithful extraction of the primary source.
PubMed Central, monograph of Ceratozamia (PhytoKeys 208): https://pmc.ncbi.nlm.nih.gov/articles/PMC9849018/ — description, type, range, altitudes, uses, preliminary status, redefinition of the species. Peer-reviewed article, open access.
Species+ (UNEP-WCMC), Ceratozamia: https://speciesplus.net/species#/taxon_concepts/13147/legal — whole genus in CITES Appendix I since 1 August 1985 and in Annex A in the European Union; the species is not listed under its own name. Official CITES and EU database; checked on 30 October 2026.
Commission Regulation (EU) 2026/1383: https://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=OJ:L_202601383 — annexes to Regulation (EC) No 338/97 in force since 29 June 2026. Official text.
BGCI PlantSearch: https://plantsearch.bgci.org/ — no garden declaring the species under either spelling. Global database of garden lists; queried on 30 October 2026.

Bibliography

Gutiérrez-Ortega, J.S., Pérez-Farrera, M.A., Vovides, A.P., Chávez-Cortázar, A., López, S., Santos-Hernández, N.G. & Ruíz-Roblero, S.K. (2021). Ceratozamia sanchezae (Zamiaceae): a new cycad species from Chiapas Highlands (Mexico). Phytotaxa 500(3): 201–216. https://doi.org/10.11646/phytotaxa.500.3.4 [Original description: types, diagnosis, description, habitat, etymology, morphometric study. Primary source.]
Martínez-Domínguez, L., Nicolalde-Morejón, F., Vergara-Silva, F. & Stevenson, D.W. (2022). Monograph of Ceratozamia (Zamiaceae, Cycadales): an endangered genus. PhytoKeys 208: 1–102. https://doi.org/10.3897/phytokeys.208.80382 [Monograph of the genus; open access.]
Martínez-Domínguez, L., Nicolalde-Morejón, F., Vergara-Silva, F., Gernandt, D.S., Huesca-Domínguez, I. & Stevenson, D.W. (2024). Evolutionary trends of reproductive phenotype in Cycadales: an analysis of morphological evolution in Ceratozamia. Annals of Botany 134(4): 631–650. https://doi.org/10.1093/aob/mcae058 [Evolution of cone characters; open access.]
Haynes, J.L. (2022). Etymological compendium of cycad names. Phytotaxa 550(1): 1–31. https://doi.org/10.11646/phytotaxa.550.1.1 [Source of the etymologies given by The World List of Cycads.]
Calonje, M., Stevenson, D.W. & Osborne, R. (2026). The World List of Cycads, version 2026.08.15. Montgomery Botanical Center, Coral Gables. https://doi.org/10.5281/zenodo.21958524 [Reference checklist.]